Some interesting fact from Wikipedia.
Daktari was based upon the 1965 film Clarence, the Cross-Eyed Lion, which also stars Marshal Thompson as Dr. Tracy and Cheryl Miller as his daughter.
Daktari (Swahili for "doctor") is an American children's drama series that aired on CBS between 1966 and 1969.
On the series, Clarence didn't do all his own stunts, he also had a stand in. Leo, another Ralph Helfer-trained lion, doubled for Clarence whenever there were any trucks involved, since Clarence spooked at the sight of these vehicles. Leo even had his own makeup artist who applied cosmetic scarring like Clarence's, so that he would resemble Clarence when photographed in closeups. This was referred to in an inside joke from the preview trailer for the movie Clarence, the Cross-Eyed Lion, that Leo (who also appeared in the MGM logo and had a gentle temperament very similar to Clarence's) was not related to Clarence.